Electrically controlled meta-switch with nonvolatile functionality

Abstract

An electrically controlled metaswitch is demonstrated by integrating passive metamaterial (metallic-slot array) with well-established nonvolatile flash memory technology [floating-gate (FG) structure]. In this hybrid configuration, the metamaterial acts as its control-gate layer while a monolayer graphene is the FG layer surrounded by insulators. Whose permittivity can be reconfigured with varying carrier density and correspondingly control the transmission of the passive metamaterial. In addition, this reconfiguration can be persistent due to the nonvolatile property of the FG structure (trapped charges). The gate-controllable light-matter interaction in this hybrid configuration can be greatly enhanced due to the strong resonances of the metallic-slot antenna; therefore, 78% ER is achieved by tuning the Fermi level from 0 to 0.4 eV at 0.24 THz. Furthermore, since the resonance frequency is controlled by the geometries of the metamaterial, it can be scaled from near-infrared to the terahertz regimes. The hysteretic behavior indicates new opportunities and versatility for reconfigurable metaswitch, allowing the persistent modification of their unusual electromagnetic responses by transient stimulus.